how to use bamboo as belly- please help (have no idea how to do it)

[james parker]

slow heatreating bamboo belly,,, just what it says,,  slower time that the boo is subjected to a heat source , soaking--  as in a bath of heat or soaking in smoke for a long period of time,, lower heat if any, or smoke only..as in a smoke house like smoking hams..if you can wait that long,, it can be better and have great effect on the belly boo , but  from my findings does not get quite as hard in compression as full char carbonizing, meaning the strip is on fire , controlled burning..

[arachnid]

When making a bamboo CORE (cut from a pole and flattened on both sides), does it need to be heat treated too? If so, on which side (facing the belly or the back)?

[dragonman]

yes it is hard to get a decent recurve with a single one piece core...(.but for a first bow I would recommend starting with a one piece core then progressing from there..)

thanks James for the info on flash carbonising, very interesting, I was aware you do this.....I never had the courage to try this, it seems to go against something inside me...!!...  so I cant comment on it,  I do believe you though , you have proved it with your bows.....maybe I'll have to try on my next one!!!... Is there an old tradition of this method of flash carbonising? or did you discover it your self?
Also how much difference does smoking the bamboo make ?  I have tried this but not seriously enough to notice any difference.
One more question..Have you ever tried Indonesian black bamboo?  It is seriously harder than moso, much harder, but the 2 times I made a bow from it the belly crysalled and virtualy collapsed, which didnt make sense to me considering its hardness!!

Dave

[PatM]

Apparently Moso is still very hard but the depth of power fibers is very minimal.

[james parker]

diameter size and compactness of power fibers can have a great deal of of varying effects also,whether on the back or belly. also age of the boo  can make a large difference,,, too young not good,, too old not good either..

as far as discovery of  flash tempering bamboo,, i discovered through trial and error,,, many many pcs were used in different stages of temper on many bows of the same design and specs, this is how i regulate  target poundage in the bow, also overbuild  , that way you keep front profile shape when tillering from the sides.
ten bows, same design, same specs,each belly boo tempered  different,, from  barely noticable to pecan color to caramel color to chocolate to all out coal black, will have tremendous changes in the end poundages,  compression will be better on the darker bellies as will the cast will be better too

[dragonman]

thanks, I'll have to try it. I believe you use a gas torch?

  yes the black(ish) bamboo was only 4" diameter, smaller than I usually use, therefore had higher crown, so could acount for the belly being crushed.

[Gaur]

Yes I wouldn't have believed it was possible.  Basically you are putting out the flames with one hand while torching with the other using a big torch.  Obviously you want to do this before you grind the bamboo or it burns the thin edges

[Gaur]

If a bowyer was to make many of these styles the difference in bamboos brings up for me the need to get it yourself so you can select the right variety and age of culms.  Or get them from a known source that selectively harvests them